Advanced Vertical Bone Augmentation with Modified Large-head Tenting Technique in Posterior Mandible

Abstract

Purpose: The objective of this study was to investigate the clinical effect of guided bone regeneration (GBR) combined with modified large-head tenting screws in the reconstruction of a mandibular advanced vertical bone defect. Materials and methods: Patients who met the inclusion criteria were included in the study. Deproteinized bovine bone was filled alone underneath the large-head tenting screws as grafting material, and the collagen membrane was covered as a barrier. About 10 months after surgery, cone-beam computed tomography (CBCT) was employed to access linear and volume changes in the augmented area, and biopsy was harvested for micro-computed tomography (micro-CT) and histological analysis during staged-implant placement. Implant survival rate and surgical-related complications were recorded. Descriptive analysis was done using Statistical Package for the Social Sciences (SPSS) software. Results: From May 2017 to September 2021, a total of 20 patients fulfilled the inclusion criteria and received large-head tenting screw-enforced GBR. There were no postoperative complications or adverse events that occurred during the healing phase. Approximately 10 months after surgery, the average linear vertical bone gain was 5.76 ± 3.14 mm (0.05–11.77 mm), with the mean linear horizontal width gain being 3.42 ± 2.56 mm (0.56–8.91 mm). The bone volume/total volume (BV/TV) and bone mineral density (BMD) were 27.55 ± 4.59% and 0.28 ± 0.05 g/cm 3 , respectively. Histological analysis of the regenerated alveolar bone revealed that the new bone percentage was 25.95 ± 6.07% (17.4–36.7%), and the percentage of the remaining scaffold was 30.95 ± 3.79% (23.1–37.0%) at 10 months, postoperatively. All implants were placed according to preoperative planning, and no implants failed after the healing phase. Conclusion: With the limitations of the study, the combination of large-head tenting screws with deproteinized bovine bone and collagen membrane appears to be a promising and exceptional technique in the reconstruction of advanced vertical bone defects in the posterior mandible.